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VisionPro IAQ thermostat - strange behavoir at midnight?

I have a VisionPro IAQ thermostat and I've noticed this strange behavior twice in the last few days. I am running 3 CPH on heat. Right around midnight, it did 3 very short runs with very little OFF time between runs, during a period of about a half hour, and then resumed normal cycling at about 3 CPH. Load is about 50% at this time, so normally runs are about 10 minutes ON and 10 minutes OFF.
11:56pm to 12:04am (8 minutes ON)
1 minute OFF
12:05am to 12:12am (7 minutes)
3 minutes OFF
12:15am to 12:23am (8 minutes)
After this, it ran several cycles of about about 10 minutes OFF and 10 minutes ON.

I have a suspicion that this is caused by the weather here. We usually have a large day-to-night temperature difference. Since I have been watching the cycling behavior, I have noticed what appears to be some short cycling well before midnight, which seems to correct itself after a while. Could it be that the PID algorithm does not handle the large drop in temperature very well, and takes some time to adapt?